MINT back in the day for Atari ST’s was a UNIX-like layer that ran on top of TOS (The Atari MS-DOS like OS) and provided basic Unix services. With the program aptly called JET (Just Enough TOS), the Macintosh 68000’s can setup a TOS compatible interrupt vector table, and run TOS procedure emulation to run the MINT binaries under MacOS!
So, it’s UNIX!
Sort of. Consider it an "Operating Environment", much like what Windows 3.1 was to MS-DOS.
You can find the binaries here:
It includes gcc 2.5.8, and a somewhat basic environment. It does have lots of potential, but the biggest gripe is that it will crash with virtual memory enabled. Also since it is 68000 based programs it is running under emulation on the PowerMAC computers. It will run on various 68k emulated MAC's namely Basilisk II.